Wall Seam Bolts

[Don in Michigan]

Hi all,

I have a 26 foot round above ground type pool that was sunk into the ground so only about 1 foot of the pool is above the ground. Pool is about 5 feet deep. Pool was in place when I bought the house 3 years ago.

Uncovered it this weekend and noticed that I can see what looked to be like 2 rows of bolt heads running up and down the side. Have since found that this is how the walls are joined together.

Question is what would have casued these bolt heads to now be visible, when I never noticed them the past 2 season we used the pool? Also, is there any remedy for this? Seems like the spots were the bolt heads are would be a prime spot for a leak.

I did have a backhoe within about 4 feet of the pool a couple weeks ago for an unrelated project. This seems to be a likely cause. Tonight I dug out the sand around the affected area, hoping that this will allow the wall/seam to flex back to where it was?

Thanks for any tips you may be able to share.

Don